Process of making cement.



UNITED STATES PATENT OFFICE.

FREDERIOKGEORGE JORDAN, SPOKANE, WASHINGTON.

PROCESS OF MAKING CEM ENT.

SPECIFICATION forming part of Letters Patent No. 702,009, dated June 10, 1902.

Application filed July 11, 1901; Serial No. 67,921. (No specimens.l

To all whom it may concern:

Be it known that I, FREDERICK GEORGE JORDAN, a citizen of the Unitedv States, residing at Spokane, inthe county of Spokane and State of Washington, have invented a new and useful Process of Making Cement, of which the following is a specification.

This invention relates tothe manufacture of Portland cement, and has for its object in a ready,expeditious,cheap,and thoroughly practical manner to effect production of a uniform and high grade hydraulic cement.-

.The manufacture'of Portland cement is usually accomplished bytwo procedures known commercially as the. wet or English. process and the dry or Germanivprocess. Both of these processes have inherent disadvantages that under the procedures as practiced are practically impossible of elimination. v

Briefly stated, under the procedure of the Wet process the separate materials, all of which are-of necessity soft in character, are first mixed, then groundsin water, thenconveyed to settling-backs, where precipitation of the materials is efiected, after which thematerials are dried by artificial .heat into large masses,and thesemasses are then broken up into lumps, which are burned and then ground to powder. The disadvantages of this procedureare that the different materials, which vary in grade and in specific gravity, precipitate irregularly, so that the resulting mixture lacks uniformity of character, and hence the product obtained is of necessity inferior in quality and practically of low grade. Further,this procedure requires large areas of settling-backs, consumes alarge amount of time in the removal of the superfluous water, and necessitates the expenditure of large sums of money in fuel to edect the evaporation of the water from the mixture tobring it to a condition Where it may be broken or disintegrated preparatory to burning.

Under the procedure of the dry process the separate materials, usually of soft or indurated character, are mixed and incorporated by dry grinding, sufficient Water being applied to the powder to present a plastic mass,

and thisis then taken and molded into blocks, which are burned and finally ground to a finepowder. The disadvantage ofthis procedure is the great cost of the grinding machinery to effect reduction offthe mixture to a powder,

and where the materials are hard in character their reduction to .the finely-divided condi- :tion necessary to the productionof a highgrade- Portland cement will, render the procure the desired results by the employment of natural forces, these to be utilized in a mannenthat will produce the highest and most satisfactory results with aminimum expenditure of both time and money.

- In carrying my process into effect I take a I 7 material containing a high percentage of lime,

such as chalk ormountain-limestone, the latterby preference to be of the class known, as

rich limestone, and this I calcine in a suitable kiln under a heat of from 1,200 to 1,500 Fahrenheit. This step may becarried into effect in any preferred manner and by theemploymentot' any character of kiln suited to the purpose, and I havefou nd in practice that by the employment of kiln separated from but.

communicating with a furnace in such man ner that while all ofthe.highly-heatedproducts of combustion are utilized to decarbonate the lime all of the ashes, smoke, and

other unconsumed products of combustion are excluded therefrom the bestresults are attained. The form of furnace employed for effecting calcination of the lime-'bearingsubstance may be an ordinary mufifle-furnace-or a coke-oven. I then take the decarbonated lime and while in an incandescent state'mix with it a predetermined quantity of clay,shale,

or other like material containing the necessary silica and alumina, this material to be in its native condition-that is to say, as taken p,

. gredients being determined by sampling and chemical analysis prior to the admixtureof the lime with thesilica and alumina bearing clays, the objecthad in View by proportion of the different materials being to secure a resultin g cement composed of from sixty-two per cent.to sixty-eight per cent.of lime with silica, alumina, and iron in a ratio approximating or somewhat exceeding three parts of the former to one part of the latter. In the selection of the raw materials I reject any that will result in a cement containing more than seven per cent.magnesia, as this is a deterrent to the production ofa high-grade cement; but the presence of a small percentage of alkali is not objectionable. The mixture of lime and clay of the character specified is discharged into an air and steam tight revoluble muller and mixer fitted with appropriate valve-controlled cold or hot water, steam, cold or hot air blasts or supplies, wherein the materials, although of variable character, are equally well and perfectly disintegrated and rapidly mixed, the rapidity with which the operation is performed being under the control of the operator by adjusting the blasts or forces according to the work to be done. The lime being perfectly decarbonated is in a condition for impalpable disintegration by natural forces-that is to say, by subjecting it in its incandescent state to either water, steam, or air, the disintegration of the lime under these conditions being rapid and perfect to impalpability. The mulleris a cylinder having its ends closed and is mounted on trunnions, whereby it may be tilted when the operation is completed, and may be built somewhat on the lines of an ordinary Bessemer converter, provision being made whereby the same shall be rotated upon its longitudinal axis, and this muller contains a plurality of loose steel balls, which under the rotation of the muller efiects rapid disintegration and perfect mixing of all of the materials. In the case where hard compact mountain-limestone is employed, to hasten disintegration an excess of either water or steam, or both, with or without air, may be employed. Under these conditions all of the steam and vapors are retained by the substances, resulting in the presentation of a hot, impalpable, homogeneous mass of any desired degree of temperature or moisture and in a perfect condition to be subsequently pressed into briquets or blocks, which harden upon cooling.

In addition to the employment of steam or water jets or blasts with some kinds of material advantageous results are secured by introducing to the mass while in the muller a solution, such as silicate of soda, which not only acts to cement the minute particles together when subjected to pressure, but readily acts as a flux in the transformation of the lime and silicates into the necessary doublesilicate of lime, forming Portland cement.

The discharge of the charge of hot, moist, impalpable materials directly into the bin or hopper of the block or briqueting machine is efiected by tilting the muller, and as the revolution of the muller continues even when tilted the charge is rapidly and cleanly discharged.

material, the small output of power required to accomplish the process, the employment of natural forces in lieu of high power, the simplicity and small cost of a plant to carry out the procedure, the comparatively small space required, the positive control of the output during the course of its preparation, and the universality of the process, it being equally suited to both soft and hard limestones.

What is claimed isl. The herein-described method of making Portland cement, which consists in decal-bonating a lime-bearing substance, mixing therewith, while in an incandescent state, a suit-' able quantity of silieious clay, and then agitating the mixture in the presence of a hydrating agent.

2. The herein-described method of making Portland cement which consists in decarbonatin g a lime-bearing substance, mixing therewith, while in an incandescent state, a suitable quantity of moist silieious clay and then agitating the mixture in the presence of a hydrating agent.

3. The herein-described method of making Portland cement which consists in decarbonating limestone, mixing therewith, while in an incandescent state, a suitable quantity of silieious clay, and then agitating the mixture in the presence of a hydrating agent.

4:. The herein-described method of making Portland cement which consists in decarbonating limestone, mixing therewith, while in an incandescent state, a suitable quantity of silieious clay and then agitating the mixture in an air-tight holder in the presence of a hydrating agent.

5. The herein-described method of making Portland cement which consists in decarbonating limestone, mixing therewith, while in an incandescent state, a suitable quantity of silieious clay, then passing the materials to an air-tight holder and introducing into the mixture a fluxing agent, and then agitating the mixture in the presence of a hydrating agent.

6. The herein-described method of making Portland cement which consists in decarbonating limestone, mixing therewith, while in an incandescent state, a suitable quantity of silieious clay, then passing the materials to an air-tight holder and introducing into the mixture a solution of silicate of soda and then agitating the mixture in the presence of a hydrating agent.

IIO

i an incandescent state, avsuitablequantity of. silicious clay, then agitating the mixture in.

7. The herein-described method of making Portland cement which consists in d'ecarhonating limestone, mixing therewith, while in the presence of a hydrating agent, and effecting thorough commingling of the materials,

then molding, then burning, and' finally reducing to a pulverulent mass. V

8. The herein-described method of making Portland cement which consists in deoarbom ating limestone, mixing therewith, while in I an incandescent state,.a suitable quantity of silicious clay, then passing the materials man" air-tight holder and introducing into the mix-.

tore a binding and'fldxing agent, and then agitating the mixture in the presence'o'f ahydi'ating agent.

In testimony that I claim the foregoing as my own I have hereto affixedmysignatn 'e in 20 thepresence of two witnesses. V FREDERICK GEORGE JORDAN.

Witnesses:

C. E. DOYLE,

FRANK S. APPLEMAN. 

